The 144-year-old church had faced a declining congregation for years, and parishioners decided its time had come.

There are now only five regular parishioners who attend mass on alternate Sundays, not counting attendees from nearby Waubra and Lexton, and it was becoming unsustainable to keep the doors open.

Fon Ryan has attended services at the church since he was a child, and has acted as an unofficial chronicler of its history, following the work of his parents.

"I'm a bit saddened by it, and a bit disappointed, but for me, it's the reality I knew was going to come," he said.

"I think it's just falling into line with what's happening in church practice with Christians in Australia, some religions go up and some go down a bit, but all the Christian religions that I know are in decline," he said.

"It's hard to answer exactly (why), but I think it's a combination of factors, the way modern people live."

Mr Ryan remembers when the church was the centre of life in the town, with baptisms, weddings, and funerals, and mission visits from the Wendouree Redemptorist monastery.

"It was crowded when I was young, and growing up," he said.

SEE INSIDE THIS HISTORIC CHURCH:

"The characteristic of country churches is the gathering of people after the mass outside, they talked for a very long time, that definitely happened at Learmonth - usually the men near one gate post and the women near the other.

"There's a choir loft in the building, a mezzanine, and there was a number of choir people, singers, and an organ up there for mass every Sunday."

The site was first granted in 1857, and the foundation stone was laid in 1873.

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The final mass, celebrated by Bishop Paul Bird, will begin at 10.30am on Sunday, and will be followed by a group photo and a barbecue lunch.

It's hoped former parishioners will be able to attend and say farewell to the building.

Into the future, Mr Ryan isn't sure what will happen, though he said he would be pleasantly surprised if it became an art gallery.

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"I'm not sure of the timetable but it will be sold, my understanding is the parish will sell it, and I would expect that as with all these sales as you watch around the country, someone buys them and lovingly restores them, subject to heritage of course, then they often become dwellings," he said.

"Some people say, yes, I've got to get back for the last mass, but for some people, they say it's sad."

The Catholic Diocese of Ballarat was contacted for comment.

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